The present invention relates to an electrophotographic sensitive member comprising a photoconductive layer formed of amorphous silicon carbide and an organic semiphotoconductive layer piled up. [Prior Arts and Problems thereof]
Photoconductive materials of an electrophotographic sensitive member include inorganic materials, such as Se, Se--Te, As.sub.2 Se.sub.3, ZnO, CdS and amorphous silicon, and various kinds of organic material. Of them, Se has been first used, and then also ZnO, CdS and amorphous silicon have been practically used. On the other hand, as to the organic materials, PVK--TNF has been first practically used, and then a separated function type sensitive member, in which a function of generating an electric charge and a function of transporting the electric charge are put in charge by separate materials, has been proposed. The organic materials have been remarkably developed by this separated function type sensitive member.
Also an electrophotographic sensitive member, in which an organic semiphotoconductive layer is piled on an inorganic photoconductive layer, has been proposed.
For example, a built-up sensitive member, in which an organic semiphotoconductive layer is piled on a Se layer, was already practically used. However, this sensitive member showed disadvantages in that Se itself is harmful and the sensitivity on the side of long wavelengths is inferior.
So, a built-up sensitive member comprising a photoconductive layer formed of amorphous silicon carbide and an organic semiphotoconductive layer has been proposed in Japanese Patent Laid-Open No. Sho 56-14241. With this sensitive member, the above described problems have been eliminated to obtain characteristics such as antipollution and high photosensitivity.
It has been, however, found from the measurement of the photosensitivity, surface electric potential and residual electric potential of such the electrophotographic sensitive member produced by the present inventors that satisfactory characteristics are not obtained yet and further improvements are required.